Al-Qaeda's deputy leader, Ayman al-Zawahiri, has said in a video the militant network will respond to attacks on Muslims in Lebanon and Gaza.

The video was broadcast by Arabic television station al-Jazeera.

Al-Qaeda could not remain silent in the face of a "Crusader war" and now saw "all the world as a battlefield open in front of us", he said.

Events in Lebanon and Gaza showed the importance of the battle in Afghanistan and Iraq, he added.

"The war with Israel is not about a treaty, a ceasefire agreement... It is rather a jihad for the sake of God until the religion of God is established. It is jihad for the liberation of Palestine, all of Palestine, as well as every land that was a home for Islam, from Andalusia to Iraq," he said.

We cannot just watch these shells as they pour wrath on our brothers in Gaza and Lebanon and sit back in submission